Abstract
We review aspects of the life histories of representative enemies of coccinellids (both entomophagous and phytophagous species) and expose both potential and real effects that they have on life parameters of their hosts. Lady beetles are attacked by a variety of natural enemies (bacteria, fungi, mites, nematodes, protozoa, wasps, flies). Few of these enemies have the ability to alter significantly the population dynamics of their hosts. This review should encourage further research to help define the role of natural enemies in the population dynamics of coccinellids. Ultimately, the conservation of beneficial lady beetles and the management of nuisance and pestiferous ones should be major emphases of research on coccinellid–natural enemy interactions.

Evans, E.W. 2009. Lady beetles as predators of insects other than Hemiptera. Biological Control 51: 255-267.

(Or: Evans, E.W. Lady beetles as predators of insects other than Hemiptera. Biological Control (2009), doi:10.1016/j.biocontrol.2009.05.011)

Abstract:

Entomophagous lady beetles often prey on a variety of insects in addition to the Hemiptera (Sternorrhyncha) for which they are well-known natural enemies. Many species (particularly those well-adapted for consuming aphids) appear opportunistic in their use of non-hemipteran prey.

Lundgren, J.G. 2009. Nutritional aspects of non-prey foods in the life histories of predaceous Coccinellidae. Biological Control 51(2): 294–305.

Abstract (part):

Non-prey foods are an integral component of the diets of most predaceous coccinellids. Under field conditions, numerous coccinellids consume nectar, honeydew, pollen, fruit, vegetation, and fungus. These non-prey foods are used by coccinellids to increase survival when prey is scarce, reduce mortality during diapause, fuel migration, and enhance reproductive capacity.

Ladybirds are probably the best known predators of aphids and coccids in the world, though this greatly underestimates the diversity of their biology. Maximising their impact on their prey is an important element in modern conservation biological control of indigenous natural enemies in contrast to the classical approach of releasing alien species.

Denemark, E. and J. Losey. 2010. Causes and consequences of ladybug washups in the Finger Lakes region of New York State (Coleoptera: Coccinellidae). Entomologica Americana, 116: 78-88.

Abstract.—We searched for and collected data on a phenomenon known as ladybug washups, in which large numbers of coccinellids aggregate on the shores of major bodies of water. Our field season lasted from 5/23/2008 until 8/12/2008 in the Finger Lakes Region of New York, United States.

ABSTRACT: Aggregations of lady beetles, predominately Hippodamia convergens and H. tredecimpunctata, were commonly observed on the shores of lakes in the Upper Midwest during the autumn and spring. The beetles remain on the shore for only a short time, usually dispersing within 2-3 weeks. Lady beetles from autumn shore aggregations and overwintering aggregations are characterized by the presence of large amounts of fat, reproductive inactivitiy, empty digestive tracts, a skew in the sex ratio favoring females and the behavioral tendency to form aggregations.

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